peterson_comsol_steps.txt

1D axi-symmetric
Comsol >> heat transfer >> conduction >> transient
specify line: 0 0.0006 0.00062 0.1
subdomain properties
needle heat source Qv = 5.3052e5 W/m3 * (1 – flc2hs(t-30, 0.01))
init 23.5C
Mesh >> Free mesh parameterss >> subdomain >> max mesh size: 1e-5 1e-7 1e-5 leads to 14,256 elements
max time step size 0.01s
range(0,0.01,1) range(2,1,60)
5 minutes to solve


3D model

3D transient heat transfer
Draw specify block (0.2, 0.2, 0.02) offset (-0.1, -0.1, -0.1). Here 0.02 is the variable thickness.
Draw specify block (0.2, 0.2, 0.18) offset (-0.1, -0.1, -0.08). 
Draw specify cylinder (r=0.0005, h=0.1, offset z = -0.05.
Draw specify points (x=zeros, y=zeros, z=0, 0.01, 0.02 0.03 0.04 0.05)
Subdomain settings
1: k=0.2, rho = 200, cp = 2050
2: k=0.1, rho = 200, cp = 2050
3: k=160, rho = 8000, cp = 460 Q = 6.355e5 (0.5 W/m) for 1-mm steel needle)
all: init = 0
Solver parameters: range(0,0.1,1) range (2,2,10) range(20,10,1000)
Free mesh parameters: 
subdomain 3: max size 0.0003, growth 1.1, press remesh.